Radio system



L. M. KNOLL.

RADIO SYSTEM. APPLICATlON FILED APR. 2, 1920.

1,394,02 Patented Oct. 18, 1921.

INVEN TOR.

fly} 4?. m By W ATTORNEY.

mam ran LLOYD a. KNOLL, or PHILADELPHIA, rnnnsynvaiim, ASSIGNOR or o mrounlzrn TO 'rnomas APPLEBY,

Application filed mini .2,

To all whom it may concern.

Be it known-that I, LLOYD M. KNOLL, a citizen of the UnitedStates,'residing in the, city and county of Pennsylvania, liaveinventednew and usefful Improvements in Radio Systems, of

. lected sources with a minimum whichthe following is a specification.

M35- invention relates to'radio signaling or control systems involvingthe transmis-;

sion through'thenatural media of electroradiant energy 01:electromagnetic waves for telegraphy, telephony or other signaling orcontrol purposes. a

My invention resides in' apparatus for the reception of electro-radiantenergy from seof interference from other sources.

. My invention further resides in apparatus for directionaldetermination of electroradiant energy sources.

My invention still further resides in coinbined uniform directional andnon-uniform directional radio absorption structure and apparatus whereinthe characteristics of both -may be combined in a highly efficient andeffect ve manner with a minimum of appa-.

ratus and adjustments.

My invention also resides in apparatus hereinafter described andclaimed.

Heretofore whenever it was necessary or 1 desirabletoreceive radiosignals from certam specific transmitt ng stations, or for the purpose.of ascertaining their direction, it i has been customary to employabsorption structure oi the so called .loop or exploriiig coil type. Thedirectional characteristics bf these-loops or coils are such that itisii'npossible to differentiate between. the

true and converse directions, both being in;-

dicated with equal facility, leaving much doubt as to whichof themrection desired' The structure .of my invention eliminates receivingsystem embodying my structure.

name SYSTEM.

Specification of Letters Patent.

1920. Serial N0.

Philadelphia, State of ipf substantially unifor indicates the di F orPHILADELPHIA, rnmvsrtvnnra 2" graphically indicates the directionalcharacteristic of the structure herein described.

Fig. 3 is a modification'of ig. I in which a multiple of non-uniformdirectional struc- "ture are employed.-

In F

eristic" is connected to earth 2 throu'gh loop 3 and the primary coil 4of radio frequency transformer 5. Shunt- 1g. 1 an ordinary radio antennal,: m d rectional charac-u;

a counter-capacity or 1 ed around the primary coil is a variable tuningcondenser 6 which mayalso be connected so as to shunt both the primarycoil and the loop as shown in Fig.3. The ar rangement thus fardescribed' constitutes the absorption, primary, or antenna circuit.

. Loop 3 consists of a rectangulanflat heli- C wound on a frame or anyother suitable round, or other suitably shaped coil,

means of support rotatively mounted on its vertical axis and of suchdimensions and convolutions of conductorthat it will absorb energy fromwith fair proportion to that ofantennal.

As well knowndn the art an ordinary an tenna, especiallyif of thevertical type, itself absorbs energy. cquallywell from all directionsand'therefoiehas a substantially passing electromagnetic waves uniformdirectional .characteristic, which, in-

refined cases, may beg'raphieally represented by a circle, asat A, 2'.

Loop 3, of the type described, when used .alone absorbs most energy'whenthe plane of its winding ,is in the line of Wave propa ,gationorat-right-angles to the wave front,

The non-uniform directional characteristic :ofisllch a loop is commonlycalled a figure eight, which" it resembles, as indicated'gra'phical'lyiby the two circles B and B'in lhe energy absorbed by andflowing in the loop is said to be dueto' phase. differ? ence between itssides; the momentary flow of energy absorbed by the antenna may be -inthe same or the opposite direction to that.

flowing in the side of the loop to which'the antenna-is connected,depending upon the di-o rection of the transmitting station and the.

position of the loop.

When passing, electromagnetic waves act on antenna .1 and the loop 3 acurrentis produced in each of them and these currents act simultaneously(for exam )le by induction, as in the case illustrated) on the de tector11. The resultant action on the detector differs from that which wouldbe produced by the antenna or the loop acting separately. If the action,on the detector, of the antenna and thcloop are equal and in phase themaximum effect will be produced in the head-telephones 14; if the saidactions are equal but opposite the minimum effect will he produce Byconnecting the absorbing loop direetly in the antenna circuit I preventany -able-coupling transformer.

harmful distortion of their resultant directional characteristic such asmay occur if the antenna alone were in the antenna circuit and the loopin the secondarycircuit and the two inductively coupled by a vari-Secondary coil 6 of transformer 5 is shunted by a tuning condenser 7 andconnected in any conventional manner to a detector type. In the caseillustrated a detector of the vacuum tube or e ectron discharge type isshown, com rising an anode or plate electrode 8, grid 9, and filament10, all inclosed in ev'acuated envelop 11. Energy for heat-- ing thefilament and thus causing it to emit electrons is supplied by a batteryor any other convenient source 12 through a regulatingresistance 13. Oneterminal of headtelephone receivers or othersuitable translating device14 is connected to the plate electrode '8 and the other terminal to thepositive side of battery 15, or its equivalent. A

variable condenser 16 is shunted across the head-telephones and battery15 for the purose of by-passing radio frequency currents in the platecircuit. connected in serieswith the grid. The connections thus showncomprise one form of .regenerativeor oscillation generating circuitand'may be'used for the reception of damped orundamped waves. It willalso be understood that any number of vacuum tubes may be added for thepurpose of amplifying the received energy. i

Fig. 2 illustrates at A, B, B and C the effects of the antenna and theloop and of the resultant effect on the detector. The resultant curveCis obtained by taking-the effect on the detector of the uniformabsorption of the'antenna as equal and in phase with theietfect on thedetector of the loop illustrated by the circle B, and as equal andopposed in phase on the detector of the loop illustrated by the circleB. The points from which curve C'is plotted will consequently beobtained by adding to the uniform B the corresponding'vector radii of B.

It will be readily understood that the'fre of any' A grid condenser 17is energy, yet at the same time kccping the absorption due to thenon-uniform absorption structure in proper proportion, a second coil 3has been added in the secondary circuit as shown in Fig. 3 whichcomprises a modification'of Fig. 1. Thetwo parallel loops or coils 3 and3 are wound on frames or other suitable means ofsupport and sufficientlyseparated. that their respective fields have little or no effect uponeach other. The frames are secured to a bar 18 to which is attached avertical shaft 19 rotatively mounted in bearings 20 and Met supportingbase 22. The upper end of base 22 comprises a compass scale and by meansof a pointer 23 secured to shaft 19 the angular bearings of interceptedstations may be readily determined.

The primary coil 4 and secondarycoil 6 of transformer 5 are so arrangedthat they may be rotated relative to each other or separated anysuitable. distance to reduce the electroma. etic coupling between themwhich re uces the energy transferred from the. rimary to .the secondarycircuit and the etector. k uch an arrangement is very useful especiallywhen strong signals are being received in order that more accurate orcloser directional reading may be obtained. v

;What I claim is: s

1. A unilateral directive radio system comprising an antenna circuitcontainingjuniform and non-uniform directional absorption structureserially connected.

2. A directional radio systemcomprising a primary circuitcontaimng'uniform and non-uniform directional absorption structure; anda secondary circuit containing non-uniform directional absorptionstructure.

3. The combination of a primary absor,- tion circuit containing uniformand nonuniform directional absorption structure and a primary coupling0011 all serially con-- nected, and a secondary circuit containing asecondary coupling coil and a translating device.

4. The combination of a primary absorp tion circuit containing uniformand nonuniform directional absorption structure,

and a primary coupling coil and a secondary circuit containingnon-uniform directional radii of A which traverse B the correspond,- ingvector radii of B, and by subtracting from the uniform radii of Awhichtraverse ing a substantially uniform directional characteristic seriallyconnected to absorption structure having a substantially non-uniformdirectional characteristic.

6. A unilateral directive radio absorption circuit comprising absorptionstructure having a substantially uniform directional characteristicserially connected .to absorption structure having a substantiallynonuniform directional characteristic, the currents of said absorptionstructures having substantially equal amplitudes.

7. A unilateral directive antenna circuit comprising a plain antenna andan absor tion' coil serially connected, and means for varying the. phaserelation of the currents of said absorption coil with respect to thecurrents of said antenna.

8. A unilateral directive antenna circuit comprising an antenna and anabsorp tion coil serially connected, and means for varying the phaserelation and amplitude of the currents of said absorption coil with re.-spectto the current-s of said antenna 9. The combination in a unilateralradio system of a plain antenna and an absorption coil seriallyconnected, and means for varying the phase relation and amplitude of thecurrents of said absor tion coil With.- respect to the currents of saicantenna.

10. A unilateral directive radio signaling system comprising incombination a plain antenna and a directive loop serially con nected toearth, and means for varying the phase relation and amplitude of thecurrents in said loop with respect to the currents in said antenna. I

11. A unilateral directive radio signaling system comprising absorptionstructure hav ing a substantially uniform directional characteristicserially connected to .a countercapacity through a rotatable iabsorptionstructure having a substantially non-uniform directional characteristic.12. In a unilateral directive radio system the combination with a plainantenna of a diretive loop and a counter-capacity all seriallyconnected.

13. A unilateral directive antenna circuit 'nected and means forcomprising a plain antenna, a directive loop, and a counter-capacity allserially connected, and means for producing in said antenna. circuitcurrents of different phase.

14. A unilateral directive antennacircuit comprising two absorptionstructures, one having a -non-uniform directional characteristic, and acounter-capacity all serially conproducing in said antenna. circuitcurrents of different phase.

15. A unilateral directive antenna circuit comprising two absorptionstructures, one having a non-uniform directional characteristic, and acounter-capacity all serially connected and means for producing in saidantenna circuits currents of different phase and amplitude.

16. A radio signaling system comprising a primary circuit containinguniform and non-uniform directional antenna structure, a secondarycircuit containing non-uniform directional antenna structure, and meansfor coupling said primary circuit to said secondary circuit.

17. A radio signaling system comprising a primary circuit containinuniform and non-uniform directional antenna structure, a secondary crcuit containing non-uniform directional an'tenna structure, and meansfor inductivelycouplingsaid primary circuit to said secondary circuit.

18. A directive radio signaling system comprising a primary circuitcontaining a non-directional antenna and a rotatable loop; a secondarycircuit containing a rotatable loop, and means for coupling said primarycircuit to said secondary circuit.

19. A directive radio si ,aling system comprising a primary circubontaining an antenna and a rotatable edit; a secondary circuitcontaining a rotatable'c'oil, and means for inductively coupling saidorimary circuit to said secondary circuit.

p In testimony whereof I have hereunto affixed my signature this 315%day of March, 1920.

LLOYD KNOLL.

